DIY: Replacing the Bearings in the Idler & Tensioner Pulleys

I replaced my tensioner pulley bearing this year but it doesn’t seem to spin as smooth as my new idler pulleys. It feels like it has more resistance, but it is smooth.

 

What torq spec did you use?

 

Ratchet. I just can’t remember how it was when I first installed it. It’s fairly new, it is smooth but is just tight. Maybe it hasn’t worn in yet

 

FWIW, in the process of research came across this excellent thread (Thank you gents!) and eventually found these on eBay. Feel like quality and the packaging is very detailed. If they are trying deceive they expended an awful lot of effort to do so.

https://www.ebay.com/itm/NEW-Koyo-Red-Seal-Idler-Pulley-Bearing-6302RMX-for-Toyota-Lexus/162780668623?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649





BTW, these sold in the listing below are probably your knock-offs. Got that same blue scheme packaging from that Chinese site.

https://www.ebay.com/itm/NEW-Koyo-Red-Seal-Idler-Pulley-Bearing-6302RMX-for-Toyota-Lexus/352168765105?rt=nc&_trkparms=aid=222007&algo=SIM.MBE&ao=2&asc=52885&meid=97b6d0abef1c445d864931194845ae8d&pid=100005&rk=3&rkt=12&sd=162780668623&itm=352168765105&_trksid=p2047675.c100005.m1851

 

@07 sport 4x4, do have links for those?

 

https://www.ebay.com/ulk/itm/322809297483

https://www.ebay.com/ulk/itm/322944401009

https://www.ebay.com/ulk/itm/322557297741

https://www.ebay.com/ulk/itm/323311393199

Verify that those are the right parts before ordering. I haven’t verified them myself, they are just on my watchlist for now until I have time to dig a little deeper.

 

Excellent, those looks like quality too, back up in case my pulleys themselves aren't in great shape when I get them out.

 

FYI, @Chuy, a note just in case anyone searches and comes across this thread. When I pulled apart the tensioner pulley on my truck (9/07 production 1GR-FE) the bearing installed was marked NSK BD17-31DUM.

Found this:
https://www.123bearing.com/bearing-BD17-31-T1XDDUM8CG-NSK.php
Describing it as:
"Deep groove ball bearing BD17-31-T1XDDUM8CG-NSK - 17x40x17.5 mm"

I used a Nachi 5203-2NS to rebuild it, which as you would expect, works fine.

 

@DaveInDenver Thanks. I remember that from mine. It's a proprietary designation as it doesn't follow the current industry standards for labeling bearings - not even from their own current standards, see page 7:
http://www.nskamericas-literature.com/en/deep-groove-ball-bearings/

 

Would this indicate a bad tensioner? Been chasing a knocking rattle sound and when I use a stethescope on the tensioner pulley bolt it sounds pretty bad, not like the other idlers.

It looks like there is play when I move it with the bolt ?

https://m.youtube.com/watch?v=sVex3eBJNDE

 

I wanted to leave my input for swapping out the tensioner bearing. I did this a couple weeks ago. I used a hammer, 11/16ths socket, a piece of cardboard, brake cleaner and 2 pieces of scrap wood (disregard impact sockets, didn't end up needing them).



The 11/16ths just about perfectly matches the inner race of the bearing. I used an SAE socket because our trucks take metric, so I didn't care if it got messed up.

Place pulley face down on cardboard - the cardboard helps protect the face of the pulley from getting gouged by the concrete. Metal on concrete = no good. Align the socket to the inner race (the inner race will be the only one showing from the rear). Then whack the aligned socket with hammer. Make sure the socket is aligned after each whack. You will be able to whack the bearing until it becomes flush with the face of the pulley.



After you've gotten the old bearing flush with the face, place it on top of the 2 pieces of wood, spaced appropriately so that they clear the bearing. Continue whacking with your hammer and aligned socket. Once you get the old bearing free, use brake cleaner and a towel to clean the gunk and build-up out of the pulley shell - since we'll be reusing it.



Place new bearing in the hole, with old bearing on top. Place socket on inner race of old bearing (see first picture). Then whack new bearing into position. The old bearing's outer race and inner race exactly line up with the new bearing's, ensuring you get uniformly applied pressure. Also, this ensures the new bearing isn't directly hit with the hammer, preventing damage.

 

This might be a good fall project

 

Shouldn't you drive on the outer race not the inner race? That way the force isn't applied to the bearings and then to the outer race?

 

When removing the old bearing it's only possible to put force on the inner race. There's a lip from the pulley shell blocking the outer race.

When installing the new bearing, I didn't have a large enough socket to line up with the outer race, so I used the old bearing as my socket.

 

The old bearing yea no problem, if you're doing this then it's probably bad anyways. I'd just hate to see someone ruin their new bearing driving it in from the center. If you're only hitting it on the outside race of the old bearing that should be fine enough, but your pictures would steer people to drive it in the same way you drove it out. Words are harder for some than others.

 

@Sandman614 may be referring to this photo, which is confusing since it appears you are driving the bearing into the pulley using the inner race. I think you just had it flipped when you snapped the photo is all. You have it oriented right in the photo with the wood blocks.

It's acceptable to remove a bearing using the inner race or really any part of the bearing you need to get it to come out if you're not reusing it. As you point out you should only use the outer race to drive in a new bearing. In this case there's no way to remove the bearing safely so it must be replaced any time it's removed due to the stop lip, as you mention.

I will also mention that you can use a big C-clamp, a long bolt or piece of threaded rod with washers & nuts with your sockets to fashion a hasty press if you don't want to use a hammer to drive them in and out.

 

OP thanks for sharing.

 

Thank you all for this write up.
Has anyone tried-verified if this pulley kit is a direct replacement without modification?
2006 V6 Prerunner sport. I'm coming up on 190K and its past time to replace.

 

@othater
Listed above in post #27. Looking at Dayco's website, the metric part# for the V6 Tacoma is

$20 7PK2120 OEM Quality Serpentine Belt

7PK2120; the eBay Dayco belt shows 7PK2119, but does cross-reference to the same belt # on Dayco's website. I'm more suspicious of the quality because Koyo's catalog does not list a bearing with a 10mm ID that would fit the Tacoma pulleys*. Could be old stock but the eBay listing does not state so. And since no reputable bearing website sells a Koyo bearing with a 10mm ID (the OEM size), I am very suspicious of the eBay listing.

* or certain Lexus models as our former ES350 3.5 V6 had same size 10mm ID bearings.